Additional Resources

Matter Learning Targets Name: Each of the following Learning Targets below are ideas or skills you need to know or do to be able to pass the unit. Circle either Yes, Need practice, or No for each learning target. If you didn t circle Yes, look over the In-Class Resources and the Additional Resources for additional help. YES = I understand or can do it Need Practice = I kind of get it No = I have no clue what I m doing Circle One Yes Need practice No Yes Need practice No Yes Need practice No Yes Need practice No Yes Need practice Learning Targets I can.. 1. Describe the relative charges, masses, and locations of the protons, neutrons, and electrons in an atom of an element. 2. Explain the arrangement of the elements on the Periodic Table, including the relationships among elements in a given column or row. 3. Explain that isotopes of an element have different numbers of neutrons and that some are unstable and emit particles and/or radiation. 4. Describe the role of valence electrons in the formation of chemical bonds. 5. Draw Bohr models for the neutral atoms of elements 1-20. In-Class Resources Additional Resources https://chemistry.osu.edu/~woodward/ch121/ch2_atoms.htm http://www.chem4kids.com/files/elem_pertable.html http://www.colorado.edu/physics/2000/isotopes/index.html http://wiki.answers.com/q/what_role_do_valence_electrons_play_in_bonding http://www.pcs.k12.va.us/tms/periodictable/index.htm http://www.slideshare.net/rachzyla/bohr-model-how-to No Yes Need practice No 6. Draw the Lewis-dot structures (electron dot diagrams) for elements 1-20. http://www.youtube.com/watch?v=ulyopnxjaz8&safe=active http://www.roymech.co.uk/related/chemistry/lewis_dot_structure.html YES = I understand or can do it Need Practice = I kind of get it No = I have no clue what I m doing

YES = I understand or can do it Need Practice = I kind of get it No = I have no clue what I m doing Circle One Yes Need practice No Yes Need practice No Yes Need practice No Learning Targets 7. Use the Periodic Table to determine the number of protons, electrons and neutrons in an atom of a given element. 8. Use the Periodic Table to determine the number of energy levels and valence electrons in an atom of a given element. 9. Describe trends across rows and down columns in the Periodic Table In-Class Resources Additional Resources http://www.college-cram.com/study/chemistry/atoms-and-molecules/using-theperiodic-table/ http://www.youtube.com/watch?v=wgz7uqmxddq&safe=active http://www.college-cram.com/study/chemistry/atoms-and-molecules/using-theperiodic-table/ http://www.youtube.com/watch?v=wgz7uqmxddq&safe=active http://chemistry.about.com/od/periodictableelements/a/periodictrends.htm http://www.chem.tamu.edu/class/majors/tutorialnotefiles/trends.htm YES = I understand or can do it Need Practice = I kind of get it No = I have no clue what I m doing

\ ~, 3 4 l' \ ~COIVMI')S 5 1 \ +) ~ 4 Be Lithium Beryllium 6.941 9.012182. 11 12 Na Mg Sodium Magnesium 22.989770 24.3050 19 20 21 K Ca Sc Potassiurrt Calcium 39.0983 40.078 37 38 Rb Sr Rubidium 85.4678 55 Cs Cesium 132.90545. Strontium Molybdenum 95.94 74 W The Periodic Table of the Elements 23 26 V Fe Osmium 190..23 108 Hs 102.90550 77 Ir Iridium AtOMi(. ~ A~mit. ~Mbo\ Atomi C.rtlA$s / W(iaht:- 78 Pt Zinc 65.39 48 Cd Mercury 200.59 112 26.981538 31 32 Ga Ge Gallium 69.723 72.61 ~4--3 -;) 4 5 ~ 49 50 In Sn Indium Tin Antimony 114.818 118.710 121.760 81 82 83 TI Pb Bi lllallillin Lead 204.3833 207.2 113 114 o ~ 1 R o W 5 0:: me.+o.. \ S : non- me.to..ls ~ N\e-teN \0 ids 1995 IUPAC masses and Approved Names from htlp:l/ww'\\'.chclll gmw,ac.ukiillpilc/atwt! masses for 107-111 from C&EN. March) 3, 1995. p. 35 112 from hllq:i!ww\-v.<'si.dehi12c.hul1l 59 Pr Protactinium 231.03588 60 61 62 63 65 66 67 68 71 Nd Pm Sm Eu Tb Dy Ho Er Tm Yb Lu NeodYlllill1n Promelhill111 Samarium Terbium Dysprosium Holmium El'bium Thulium Ytterbium Lutetium 144.24 (145) 150.36 16250 164.93032 167.26 173.04 92 93 94 8 99 100 102 U Np Pu Cf Es Fm No Uranium 244) 251) (252 Liquid S ~f room t-e.ry' pe.rq.. tvv' e...... most: re ~ <...1i\J -e.. e le.rne.)'\ \-$

Atomic # Element Name Radius 3 Lithium 152 4 Beryllium 111 5 Boron 86 6 Carbon 77 7 Nitrogen 70 8 Oxygen 73 9 Fluorine 72 10 Neon 71 11 Sodium 186 12 Magnesium 160 13 Aluminum 143 14 Silicon 118 15 Phosphorus 108 16 Sulfur 106 17 Chlorine 99 18 Argon 97 19 Potassium 232 20 Calcium 197 Column/Group/Family Names 1: A\ ~~\\ne Me:\-cd$ 2: Mko.\ir\t Eo.f"'f-h M~to-ls 3: Boron Fc,..mi l~ 4: Co.rb"n ~OlY\i I~ 5. Nd-ro~~ni;..m,I"1-6.~~e.n ~o.rnil~ 7. "Q..\Q%o..=O\S~ _ 8. Noble 1iCl.S es Particle Charge Mass Location Proton -+-\ I ~t"\u Nvc...\ e.us Neutron 0 \ Pt.MV \,1\.><" \ eus Electron... \ '4'00 AH\j tf\er~1.( Lt\le\~ v The number of protons = the o.tomlc nvrnber The number of electrons = t be 0..-\-omi c.. Y\v mbet"' The number of neutrons = RO\Jnc.\e& o..t()mit mclss - o.:h;>mi<.. rwmber The atomic number, or the number of ~r()\-ohs tells you the identity of an atom. Isotopes are elements that have the same number of VV'" C) fo\,\$,but different numbers of O~ v ~y-()n S. An ion is a cho.r~eo atom. Ions become charged by gaining or losing e\e,c...-n-o't\s Columns Columns go ~p c..nq Qc:>wn on the Periodic Table. Columns are also called ~ and ~m\ \\t..s. The column number tells you the number of \/<:A \ en<.e. Valence electrons are the electrons in the O\ltS \ d.~ Rows Rows go hoy"\"2.onto..\l\.j- on the Periodic Table. Rows are also called e.~\ods. Rows tell you the number of t,y\trc!l,c le:.\lt-ls electrons. energy level. Alpha Decay: Beta Decay: Gamma Decay: Alpha Decay Example: Beta Decay Example: _

Science Spectrum Answer Key continued 6. In both cases, the variables are directly related. As one changes, the other changes in the same direction. 7. pressure and amount of gas 8. Direct; as one variable increases, the other variable increases. 9. Yes; a straight-line graph shows a proportional relationship. 10. Boyle s law 11. Inverse; as one variable increases, the other decreases. Review 1. The particles in a gas bump each other and the walls of the container, producing pressure. 2. Gay-Lussac s Law; as temperature increases, pressure increases. In summer, the temperature of the air inside the tires would be higher than in the winter and pressure would increase. 3. The temperature of the particles in the balloon would increase. When temperature increases, the volume of the gas will increase and the balloon will increase in volume and may break. Charles s law predicts this result. 4. Temperature and pressure are inversely related. As one variable increases, the other decreases. 5. Students should draw a graph with temperature on the x-axis and pressure on the y-axis. They should draw a straight line from the origin to the top right corner. Possible title: Pressure Versus Temperature for a Gas at a Constant Volume Chapter 4 Atoms SECTION 1 THE DEVELOPMENT OF ATOMIC THEORY 1. the Greek word atomos OR a Greek word meaning unable to be cut or divided 2. There was no evidence to support it. 3. Dalton had scientific evidence to support his theory. 4. 24 g 5. New observations did not support Dalton s theory. 6. the anode 7. Charged particles move in response to a magnet, but light rays do not. 8. In Thomson s model, the atom contains smaller particles. In Dalton s model, the atom was indivisible. 9. They would either pass straight through or be deflected slightly. 10. He repeated the experiment. 11. Student should label the nucleus positive and the electrons negative. Review 1. Rutherford s experiment showed that the positive charge in an atom is concentrated in a nucleus at its center. 2. Possible answer: The law of definite proportions states that the relative masses of elements in a compound are always the same. 3. Both Dalton and Democritus thought that an atom was a tiny, indivisible particle. 4. In Thomson s atomic theory, electrons were embedded in a mass of positive charge. In Rutherford s atomic theory, electrons orbited a dense, positively charged nucleus. 5. He concluded that the particles came from atoms in the cathode and that the particles were the same in atoms of different elements. 6. There are 164 g of nitrogen in 200 g of ammonia. 7. There are 27 g of hydrogen in 150 g of ammonia. SECTION 2 THE STRUCTURE OF ATOMS 1. protons and neutrons 2. The mass of an electron is much smaller than the mass of a proton. 3. two 4. They have the same number of protons as electrons. 5. the electric force 6. It has 13 protons and 13 electrons. 7. They can have different numbers of neutrons. 8. one 9. atomic number 8; mass number 16 10. 17 11. 18 12. the unified atomic mass unit 13. 35.453 u Copyright by Holt, Rinehart and Winston. All rights reserved. Interactive Reader 5 Answer Key

Science Spectrum Answer Key continued 14. the basic unit used to measure the amount of a substance 15. 29 g 16. 24.3 g/mol 17. molar mass of Cu 63.55 g/mol; (3.20 mol Cu) (63.55 g Cu/mol Cu) 203 g Cu 18. molar mass of C 12.01 g/mol; molar mass of H 1.01 g/mol; molar mass of CH 4 (12.01 g/mol) + (4) (1.01 g/mol) 16.05 g/mol Review 1. Mass number is the number of protons and neutrons in the nucleus of an atom. Atomic mass is the mass of a single atom in grams or in unified atomic mass units. 2. top row: 7 second row: 7 third row: 27 fourth row: 37 bottom row: 87 3. Atoms A and B have the same atomic number but different mass numbers, so they are isotopes. 4. Atom D contains 37 protons. Since atoms are neutral, it must also contain 37 electrons. 5. molar mass of glucose 180.2 g/mol; (300 g glucose) (180.2 g/mol) 1.66 mol SECTION 3 MODERN ATOMIC THEORY 1. It must gain energy. 2. lost 3. Bohr s model worked only for hydrogen. 4. a region in an atom in which an electron is most likely to be 5. Student should label the large shaded region around the nucleus orbital. 6. In both models, electrons can be located only in certain energy levels. 7. the first and second 8. electrons in the outer energy level of an atom 9. two 10. They lie along different directions in space. 11. 10 12. the lowest state of energy of the electron 13. Student should label the image with both electrons in one energy level ground state and should label the other image excited state Review 1. s or p 2. Energy levels contain orbitals. 3. The first energy level contains two electrons. The second energy level contains the other five electrons. 4. An atom of nitrogen has two electrons in the first energy level and five in the second. The second energy level is the outermost energy level, so nitrogen has five valence electrons. 5. We can t know an electron s exact location, speed, or direction in an atom. 6. The electrons in an aluminum atom are located in the first, second, and third energy levels. 7. It has two electrons in the first energy level, eight in the second energy level, and three in the third energy level. The third energy level is the outermost energy level, so aluminum has three valence electrons. Chapter 5 The Periodic Table SECTION 1 ORGANIZING THE ELEMENTS 1. atomic mass 2. Scientists had not yet discovered elements with the properties that fit the pattern. Mendeleev predicted that scientists would find those elements. 3. Te and I did not fit the pattern of chemical properties unless they were put in the wrong order of atomic mass. 4. atomic number 5. The group it is in; elements in a group have similar chemical properties. Properties of elements change across a period. Review 1. The chemical properties of oxygen are more similar to those of sulfur because they are members of the same group. Elements in the same group share similar properties. Copyright by Holt, Rinehart and Winston. All rights reserved. Interactive Reader 6 Answer Key

The Periodic Table Journey Today you are going to go on a journey of discovery about the periodic table. To make it even more realistic, you are actually going to travel on a journey. The information that you need is placed around the school and you will travel to find it. To make this work we have to have some ground rules, so here goes: 1. You must stay with your group. 2. Go in order the locations are listed for each section, when you finish one go to the next one down the list. 3. Only one group at a spot at a time. 4. You may not bother any other classes. 5. You may not be loud in the hallways. Please write all of your answers in this packet and then place this in your 3-ring binder. Have a pleasant journey and don t forget to write! Transition Metals (Door W1) 1. Where do you find the transition metals on the Periodic Table? (If you haven t been to the The Periodic Table spot or through the Label Loop, you won t be able to answer this question yet.) They are found in the middle of the Periodic Table (the shorter columns). 2. List 5 properties that transition metals have. A. B. C. D. E. 3. What are the only magnetic transition metals? 4. List some special properties of the following transition metals: Platinum: Nickel: Silver: Iron:

Nonmetals (Door W2) 1. Where do you find the nonmetals on the Periodic Table? (If you haven t been to the The Periodic Table spot or through the Label Loop, you won t be able to answer this question yet.) On the right side of the Periodic Table 2. What nonmetals are solids at room temperature? 3. What nonmetal is a liquid at room temperature? Bromine 4. List some special properties of the following nonmetals: Hydrogen: Helium: Carbon: 5. What nonmetals are present in the air that you breathe? Isotopes (Door W3) 1. What is the definition of an isotope? Isotopes are atoms with the same number of protons and different numbers of neutrons. 2. What is the Nucleon Number? The nucleon number is the sum of the protons and the neutrons. 3. What is the name that we have been using for the nucleon number? Atomic Mass 4. What two isotopes are listed on the poster? Carbon 12 and Carbon - 14 5. What is the difference between the two isotopes from the question #4? Carbon 14 has two more neutrons than Carbon 12. 6. What is the same for the two isotopes from question #4? Both isotopes have the same number of protons.

What is an Element? (Door E4) 1. What is the definition of an element? 2. How many of the known elements are naturally occurring? 3. What are allotropes? Give an example. Allotropes are different forms of the same element. Coal, graphite and diamond are all allotropes of carbon. 4. What are the two most abundant elements in the Universe? Hydrogen and Helium 5. What are the five most abundant elements in your body? What percent of your body do they make up? 6. What are the two rarest elements on earth? How to Read the Periodic Table (Door E3) 1. What does the atomic number tell us about an element? The atomic number tells you the number of protons and electrons in an atom. 2. What does the atomic weight (mass) tell us about an element? The atomic weight (mass) is the sum of the protons and neutrons in an atom. 3. What do the rows on the Periodic Table tell us? The row number tells you the number of energy levels (rings of electrons) that an atom has. 4. What do the columns on the Periodic Table tell us? The columns tell you the number of valence electrons an atom has. 5. How do you find the number of neutrons that an atom of an element has? # of neutrons = atomic mass atomic number

Metals (Main Office Door) 1. Where do you find the metals on the Periodic Table? (If you haven t been to the The Periodic Table spot or through the Label Loop, you won t be able to answer this question yet.) You find the metals on the left side of the Periodic Table. 2. List six common properties of metals: A. B. C. D. E. F. 3. What are alloys and why are they so useful? 4. What are ores? 5. Why are metalloids? Metalloids are elements that have properties of both metals and non-metals. The Periodic Table (Door E2) 1. Who drew up the first periodic table? When did he do this? Dmitri Mendeleev 2. What are the columns called? Groups or Families 3. What are the rows called? Periods 4. What happens to the size of the atoms as you go across a row (period)? 5. What happens to the size of the atoms as you go down a column (group)?

6. How can we use the Periodic Table to make predictions about elements and compounds? Active Metals (By Our Fire Exit Door) 1. Where do you find the active metals on the Periodic Table? 2. Why do we call them active metals? We call them active metals because they are very reactive. 3. What do all of the Alkali Metals have in common? 4. What do all of the Alkali-Earth Metals have in common? 5. Which two active metals are radioactive? 6. What is one of the earth s most abundant metals? Where do you find it in you? Calcium is one of the most abundant metals on Earth. You have calcium in your bones. 7. What active metals do our bodies need small amounts of? Sodium and Potassium The Label Loop Starting at A207 (that room sounds familiar) go around the loop and label the things on your Periodic Table. You will need an assortment of colored pencils for your group (eight should do it). When you get back to A207, you are done with this station.

Protons, Neutrons, and Electrons Practice Worksheet Element Name Atomic symbol Atomic Mass (rounded) Atomic number Protons Neutrons Electrons Valence Electrons Metal, Metalloid or Non - metal Boron B 11 5 5 6 5 3 Metalloid Sodium Na 24 11 11 13 11 1 Metal Gallium Ga 68 31 31 37 31 3 Metal Yttrium Y 89 39 39 50 39 3 Metal Copper Cu 64 29 29 35 29 1 Metal Technetium Tc 98 43 43 55 43 7 Metal Lead Pb 207 82 82 125 82 6 Metal Ytterbium Yb 173 70 70 103 70 2 Metal Actinium Ac 227 89 89 138 89 5 Metal Molybdenum Mo 96 42 42 54 42 6 Metal Thallium Tl 204 81 81 123 81 5 Metal Fermium Fm 257 100 100 157 100 8 Metal Nobelium No 259 102 102 157 102 2 Metal Hydrogen H 1 1 1 0 1 1 Non-metal Carbon C 12 6 6 6 6 4 Non-metal Nitrogen N 14 7 7 7 7 6 Non-metal Barium Ba 137 56 56 81 56 4 Metal Helium He 4 2 2 2 2 2 Non-metal Calcium Ca 40 20 20 20 20 2 Metal Silicon Si 28 14 14 14 14 4 Metalloid Argon Ar 40 18 18 22 18 8 Non-metal Magnesium Mg 25 12 12 13 12 2 Metal Seaborgium Sg 265 106 106 159 106 6 Metal

Periodic Table Puzzle - Answer Key Down: 1. IRON - I have 26 protons. 3. HYDROGEN - I am not really an alkali metal, but since I have only 1 electron I behave like them. 4. NICKEL - I am a metal with 28 electrons. 7. ALUMINUM - I am a member of the boron family and am the most abundant metal in the Earth s crust. 8. OXYGEN - I am a gas with 8 protons and 8 neutrons. 10. LEAD - I am a member of the carbon family often mistaken for the end of your pencil. 12. MERCURY - I am a metal that is liquid at room temperature. 14. SILVER - My atomic number is 47 and I am used to make photographic film. 15. CALCIUM - I have 20 neutrons and am found in your teeth and bones. 16. PHOSPHORUS - I am a member of the nitrogen family with 16 neutrons. 18. FLUORINE - I am a gas with a mass number of 19. 19. POTASSIUM - I am the first element in the fourth period used in making fertilizer. 22. TIN - You can find me in the carbon family in the fifth period. Across: 2. CHLORINE - My atomic mass is 35.453. 5. SULFUR - I have 2 electrons in the first shell, 8 in the second shell, and 6 in the third shell. 6. CARBON - I am the head of the carbon family known as the basis of life. 9. GOLD - My atomic number is 79. 11. MANGANESE - I am a transition metal with 25 electrons. 13. NITROGEN - I make up 78% of the air and am found in the 15th group. 14. SODIUM - I am a silvery white metal used to make salt. 17. MAGNESIUM - I am a member of the alkaline earth metals used to make fireworks and medicines. 20. HELIUM - I am a noble gas with 2 electrons. 21. SILICON - I am the 2nd most abundant element in the Earth s crust and have 14 neutrons. 23. IODINE - I am a member of the halide family with an atomic number of 53. 24. ZINC - I am a transition metal with 30 electrons useful in making paint. 25. BROMINE - I am the only element in the halide family that is a liquid.

History of the Atom Notes Fill in the following table: Who and When Democritus 400 BC What Said that all matter was made out of atoms. He didn t have any evidence to back up his model. Aristotle 350 BC John Dalton J.J. Thomson Ernest Rutherford Chadwick Said that all matter was a combination of the Four Essential Elements: Air, Fire, Water and Earth. He didn t have any evidence to back up his model, but his idea was accepted as truth for 2,000 years. Said that all matter was composed of atoms. AN atom was a solid, positively charged particle (like a jaw breaker or a marble). Dalton is credited with discovering the proton. Dalton had evidence to back up his model. Using cathode rays, he discovered the electron - a negatively charged particle in the atom. Thomson s model of the atom was of a chocolate chip cookie. The cookie part was the positively charged stuff from Dalton s Model and the chocolate chips were the electrons embedded in the cookie. Performed the famous Gold Foil Experiment. He discovered the nucleus. Rutherford s model of the atom was of a nucleus (where the protons were located) in the center with electrons orbiting around it. Discovered the neutron. The neutrons were determined to be in the nucleus of the atom.

Niels Bohr Developed the Bohr Model of the Atom where you had a nucleus with protons and neutrons and the electrons orbiting around it in specific orbitals. Electrons couldn t be just anywhere. Werner Heisenberg and Erwin Schrödinger Their discoveries lead to the modern Electron Cloud Model of the Atom. In this model the electrons are everywhere, but the most likely place to find them is in Bohr s orbitals.

Name: Hour: Date: Chemistry: Atomic Number and Mass Number Complete the following chart and answer the questions below. Number of Protons Atomic Number Element Name b r; 8 ff 8 fb I { 0 1 G 6 hydrogen Grbot., hydrogen ( nitrogen ( '1 ( { "'rclh:>~~ U rq t\,'t.d",., ~0 cesium ~!~ L.\""- 11 tungsten 13 ~1V\.,'ho &V'~.'4 """"' silver 3 2 '7 14 2 146 d-3r' S'~ 82 ( :Sf) LJ 12 J.3 9~ L('J 47 b I 108 'It{ SS- '1t.{ 110 tol(.ss- 45 80 24 ~r 52 (,3 63 89 152 L(') l1"j bo 107 0(, 76 CJ"S "","1'tA"-. 14 1 ex V( c..kto~'~~ 12 0 I 92 ~; lvev- Mass Number b carbon O'A.,.... Numberof Neutrons ICfo 114 How are the atomic number and the number of protons related to each other? Ato~~/c. 41 r =: -4 of- Al:> fot\.~ How do the number of protons, number of neutrons, and the mass number relate to each other? p rcf"ot'\.5 -+ p\euft'"d1/\.5 =- f\-.pcs s 'f:/ What is the one thmg that determines the identity of an.atom (that is, whether it is an oxygen atom or a carbon atom, etc.)? n<>- p.--"" 10",,-

Atomic Theory and the Periodic Table L M6NO o L o M F S o 7 B H 0 R... o H 10 11 EN6Reo)' r: 0 b L l--l 0 T :r 12 s o 6 0 E tv.s T (] on

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The Great Periodic Table/Atomic M&M Treasure Huntl Today you are going on a treasure hunt. Your goal is to unlock the secrets of the Periodic Table! Each clue, each new discovery will unlock the Periodic Table's secrets and lead to more clues which will lead you to even deeper mysteries and even greater understandings! I am not kidding when I say that the Periodic Table is the single most important scientific document ever made. The Periodic Table is the ingredients list for the Universe - if you understand how it works, you understand the basis of EVERYTHING! Good luck and, as the great Sherlock Holmes would say, "The hunt is on!" Part One: The Plan The plan for you today is to build Bohr Models of atoms using your Periodic Table and M&Ms. Think of today as your chance to put everything together that we have learned so far and to take your understanding of the Periodic Table to new levels. Materials Each person will need to get 60 M&Ms for this lab (3 different colors, 20 of each color). Each person will need to put his or her M&Ms a double layer of paper towels. One large sheet of white paper per person (on the workbench in the lab area). Each person will need his/her Periodic Table. DO NOT EAT ANY M&Ms UNTIL YOUR ENTIRE GROUP IS DONE WITH THE LABII!! Part Two: The Set-Up 1. Get all of your materials. 2. Divide your M&Ms into three groups (based on color). Label one group protons, one group neutrons and the last grou'p electrons. 3. Draw three big concentric circles on your white sheet of paper. The smallest should be at least 4" across. These will represent the energy levels where the electrons go. Part Three: The Lab 1. You are going to fill out the information on the tables on the next 2 pages. You need to build the model first and then fill out the corresponding part of the table. I have done Hydrogen as an example for you. 2. While you are going through this activity, look for any connections between the element model and its' placement on the Periodic Table. 3. Use your Periodic Table as necessary. 4. Work with your partners. Don't get ahead of your lab group! NOTE: When your 9f.Q.MP has filled out the tables, you are cleared to eat your M&Msl

Element Cl 7J Bohr Model Atomic #of #of Atomic #of # of Energy # of Valence 0 0 c :E Drawing # Protons Electrons Mass Neutrons Levels Electrons 3 ~ ~ ~ H On 1 1 lp~ Ie 1 1 1 1 0 1 1 Li 1 2 Be B C N 5 2 a 6 2 F Ne ~~~ I~ J 4 p \ t 3 3 3 7 4 2 1 2 2 ~ 4 4 4 9 5 2 2 S,., ) ) ~p \ '\ 3 2 J...~ 3e. 5 5 5 11 6 2 3 b""l J ) b '), 4 2 t 5~)L 6 6 6 12 6 2 4 r-,p ') ) 'I ~ ~ " / / "1 f ) ') ~t., J..~ ~e J J 7 7 7 14 7 2 5 8 8 8 16 8 2 6 qpj \ 7 2 ;)<! 1~ 9 9 9 19 10 2 7 (~) ) top' " \ 8 2 :<t2. z~ 10 10 10 20 10 2 8 (o~ ) /

Build models of the elements below. Fill out the table as you go along. Work with your group - don't get ahead of your partners! Look for any patterns/similarities with an element and its' place on the Periodic Table. Element ~~ Na Mg AI Si P ]:J Bohr Model Atomic #of #of Atomic #of # of Energy # of Valence 0 c :E Drawing # Proton Electrons Mass Neutrons Levels Electrons 3 ~ =l:t: s Up '\ '\ '\ 1 3 t ~ ~Q.. ~ (e.- II 11 11 23 12 3 1 VI) ) ) l~p'1 "\ \ 2 3 fd ~C2. 1e ~~ 12 12 12 24 12 3 2 '" ) )) 3 3 5 6 3 CI 7 3 Ar 8 3 l~p,, \ 1«., ~~,~ ~"- 13 13 13 27 14 3 3 ') ~ "\ 4 3 r"p ~ &- t{f<- 14 14 14 28 14 3 4 ('1Y1 ) ) J \ \ ~ 5 3 {Sf' ~ 15 15 15 31 16 3 5 {6Y1 ~~ )ft-5~ (b? '\ ') ') (6 2..e. ~e... ~ e.. h ) -) ) {~f \ '\ ~ (<l ;<e. ~ e 011:- ~ J / ) lif' '" \ \, ~~7 ~~. ~)~, 16 16 16 32 16 3 6 17 17 17 35 18 3 7 18 18 18 40 22 3 8

Part Four: Searching For the Clues In this section, you are going to look for patterns/similarities/trends in the rows and the columns of the Periodic Table. Use your tables from above and your Periodic Table to answer the following questions. Look for clues in the numbers and in your drawings. Part 1: The Rows The two tables that you filled out are for the 2 nd and 3 rd rows of the Periodic Table. Look at each row carefully. 1. What thing(s) remain the same for each element in a given row? The number of energy levels remains the same for elements in the same row. 2. A trend or pattern is a regular, consistent change (i.e. as we go from winter to summer, the temperature trends upward). What trends or patterns do you see as you go from left to right across the 2nd row? (Find at least three.) The number of protons, electrons and valence electrons all increase by one as you go across the row. The atomic mass increases and the number of neutrons generally increases. 3. Do the trends and patterns that you discovered in question #2 hold true for the third row of the Periodic Table, too? Yes 4. Look over the rest of the Periodic Table. Do your trends/patterns hold true for all elements? Yes 5. Share your findings with the group next to you. Did they find the same clues? Write down any new clues that they found. 6. Show your findings to the teacher and get his initials here: _

Part 2: The Columns The two tables that you filled out represent columns 1-8 of the Periodic Table (only the first few elements of each column). 1. What thing(s) remain the same for each element in a given column? The all have the same number of valence electrons. 2. A trend or pattern is a regular, consistent change (i.e. as we go from winter to summer, the temperature trends upward). What trends or patterns do you see as you go down a column? (Find at least three.) The number of energy levels goes up by one as you go down a column. The number of protons, electrons and neutrons increases as you go down a column. 3. Do the trends and patterns that you discovered in question #2 hold true for all of the columns? Yes 4. Look over the rest of the Periodic Table. Do your trends/patterns hold true for all elements in each column? Yes 5. Share your findings with the group next to you. Did they find the same clues? Write down any new clues that they found. 6. Show your findings to the teacher and get his initials here: _

Part Five: Sharing Your Findings with the Class For this part, we are going to come up with a class list of the trends, similarities and patterns that we discovered on the Periodic Table. Write down the agreed upon items below: Row Clues: Column Clues:

Part Six: Blazing a New Traill Trends, patterns and similarities are no good if you can't use them. You are going to take what you have learned and predict the properties of elements that haven't even been discovered yet! This is exactly what scientists do - they take what they know and use it to help them discover new things! In the table below, I want you to tell me about the as yet undiscovered elements from row 8 of the Periodic Table. To make things a little easier, we will only do the elements for columns 1 through 8 (the ones you numbered at the top of your Periodic table). <1 1:J Bohr Model Drawing Atomic # #of #of Atomic #of #of #of 0 0 c :E (draw the rings, but Protons Electrons Mass Neutrons Energy Valence 3 ::s :t:t: only label the outside Levels Electrons :t:t: ring electron number) 1 8 f1~p )))))) '\ 119 119 119 8 1 J~ - - ). ))1) ~I~ 2 f~of 8 120 120 120 - - 8 2 3 8 133p ))))) ~I)~ 133 133 133 - - 8 3 4 8 jj))) 13'fp ~ ~~ 134 134 134 - - 8 4 5 8 (3~p ))))))/ ~ 135 135 135 - - 8 5 6 8 (~bf))))) ) ~~ 136 136 136 - - 8 6 7 8 13 1 t))j)))) }- 137 137 137 - - 8 7 8 8 (~rf I J))) )) ~e 138 138 138 - - 8 8,

Lewis - Dot Structures In chemistry, the valence electrons are the most important thing to keep track of for an atom. A Lewis-Dot structure is a way of showing just the valence electrons of an atom. oe H He 0 Q., -. Li Be B C. N. : o. : F. : Ne '» -. ~- -. No Mg AI Si. p. : S. : CI- :Ar: K Co Things to know for this unit's test: - Knowthe history of the atom (who discovered what part) - Knowthe three parts of the atom, their charges, masses and where you find them) - Knowhow to draw Bohr Model Diagrams - Knowhow to draw Lewis-Dot Structures - Knowhow to read your Periodic Table (protons, neutrons, electrons, energy levels, valence electrons, trends in rows and columns)

The Periodic Table of the Elements (with Ionization Energies) 1 18 Hydrogen 1 H 1.01 1312 2 Alkali metals Alkaline earth metals Transition metals Lanthanides Actinides Other metals Metalloids (semi-metal) Nonmetals Halogens Noble gases Element name Symbol First ionization energy (kj/mol) Mercury 80 Hg 200.59 1007 Atomic # Avg. Mass 13 14 15 16 17 Helium 2 He 4.00 2372 Lithium 3 Li 6.94 520 Beryllium 4 Be 9.01 900 Boron 5 B 10.81 801 Carbon 6 C 12.01 1087 Nitrogen 7 N 14.01 1402 Oxygen 8 O 16.00 1314 Fluorine 9 F 19.00 1681 Neon 10 Ne 20.18 2081 Sodium 11 Na 22.99 496 Magnesium 12 Mg 24.31 738 3 4 5 6 7 8 9 10 11 12 Aluminum 13 Al 26.98 578 Silicon 14 Si 28.09 787 Phosphorus 15 P 30.97 1012 Sulfur 16 S 32.07 1000 Chlorine 17 Cl 35.45 1251 Argon 18 Ar 39.95 1521 Potassium 19 K 39.10 419 Calcium 20 Ca 40.08 590 Scandium 21 Sc 44.96 633 Titanium 22 Ti 47.88 659 Vanadium 23 V 50.94 651 Chromium 24 Cr 52.00 653 Manganese 25 Mn 54.94 717 Iron 26 Fe 55.85 763 Cobalt 27 Co 58.93 760 Nickel 28 Ni 58.69 737 Copper 29 Cu 63.55 746 Zinc 30 Zn 65.39 906 Gallium 31 Ga 69.72 579 Germanium 32 Ge 72.61 762 Arsenic 33 As 74.92 947 Selenium 34 Se 78.96 941 Bromine 35 Br 79.90 1140 Krypton 36 Kr 83.80 1351 Rubidium 37 Rb 85.47 403 Strontium 38 Sr 87.62 550 Yttrium 39 Y 88.91 600 Zirconium 40 Zr 91.22 640 Niobium 41 Nb 92.91 652 Molybdenum 42 Mo 95.94 684 Technetium 43 Tc (98) 702 Ruthenium 44 Ru 101.07 710 Rhodium 45 Rh 102.91 720 Palladium 46 Pd 106.42 804 Silver 47 Ag 107.87 731 Cadmium 48 Cd 112.41 868 Indium 49 In 114.82 558 Tin 50 Sn 118.71 709 Antimony 51 Sb 121.76 834 Tellurium 52 Te 127.60 869 Iodine 53 I 126.90 1008 Xenon 54 Xe 131.29 1170 Caesium 55 Cs 132.91 376 Barium 56 Ba 137.33 503 57-70 * Lutetium 71 Lu 174.97 524 Hafnium 72 Hf 178.49 659 Tantalum 73 Ta 180.95 761 Tungsten 74 W 183.84 770 Rhenium 75 Re 186.21 760 Osmium 76 Os 190.23 840 Iridium 77 Ir 192.22 880 Platinum 78 Pt 195.08 870 Gold 79 Au 196.97 890.1 Mercury 80 Hg 200.59 1007 Thallium 81 Tl 204.38 589 Lead 82 Pb 207.20 716 Bismuth 83 Bi 208.98 703 Polonium 84 Po (209) 812 Astatine 85 At (210) 890 Radon 86 Rn (222) 1037 Francium 87 Fr (223) 380 Radium 88 Ra (226) 509 89-102 ** Lawrencium 103 Lr (262) 470 Rutherfordium 104 Rf (267) 580 Dubnium 105 Db (268) Seaborgium 106 Sg (271) Bohrium 107 Bh (272) Hassium 108 Hs (270) Meitnerium 109 Mt (276) Darmstadtium 110 Ds (281) Roentgenium 111 Rg (280) Copernicium 112 Cn (285) Ununtrium 113 Uut (284) Ununquadium 114 Uuq (289) Ununpentium 115 Uup (288) Ununhexium 116 Uuh (293) Ununseptium 117 Uus (294?) Ununoctium 118 Uuo (294) *lanthanides Lanthanum 57 La 138.91 538 Cerium 58 Ce 140.12 534 Praseodymium 59 Pr 140.91 527 Neodymium 60 Nd 144.24 533 Promethium 61 Pm (145) 540 Samarium 62 Sm 150.36 545 Europium 63 Eu 151.97 547 Gadolinium 64 Gd 157.25 593 Terbium 65 Tb 158.93 566 Dysprosium 66 Dy 162.50 573 Holmium 67 Ho 164.93 581 Erbium 68 Er 167.26 589 Thulium 69 Tm 168.93 597 Ytterbium 70 Yb 173.04 603 **actinides Actinium 89 Ac (227) 499 Thorium 90 Th 232.04 587 Protactinium 91 Pa 231.04 568 Uranium 92 U 238.03 598 Neptunium 93 Np (237) 605 Plutonium 94 Pu (244) 585 Americium 95 Am (243) 578 Curium 96 Cm (247) 581 Berkelium 97 Bk (247) 601 Californium 98 Cf (251) 608 Einsteinium 99 Es (252) 609 Fermium 100 Fm (257) 627 Mendelevium 101 Md (258) 635 Nobelium 102 No (259) 642

The Periodic Table of the Elements (including Atomic Radius) 1 18 Hydrogen 1 H 1.01 31 2 Alkali metals Alkaline earth metals Transition metals Lanthanides Actinides Other metals Metalloids (semi-metal) Nonmetals Halogens Noble gases Element name Symbol Atomic radius (picometers) Mercury 80 Hg 200.59 132 Atomic # Avg. Mass 13 14 15 16 17 Helium 2 He 4.00 28 Lithium 3 Li 6.94 128 Beryllium 4 Be 9.01 96 Boron 5 B 10.81 84 Carbon 6 C 12.01 76 Nitrogen 7 N 14.01 71 Oxygen 8 O 16.00 66 Fluorine 9 F 19.00 57 Neon 10 Ne 20.18 58 Sodium 11 Na 22.99 166 Magnesium 12 Mg 24.31 141 3 4 5 6 7 8 9 10 11 12 Aluminum 13 Al 26.98 121 Silicon 14 Si 28.09 111 Phosphorus 15 P 30.97 107 Sulfur 16 S 32.07 105 Chlorine 17 Cl 35.45 102 Argon 18 Ar 39.95 106 Potassium 19 K 39.10 203 Calcium 20 Ca 40.08 176 Scandium 21 Sc 44.96 170 Titanium 22 Ti 47.88 160 Vanadium 23 V 50.94 153 Chromium 24 Cr 52.00 139 Manganese 25 Mn 54.94 139 Iron 26 Fe 55.85 132 Cobalt 27 Co 58.93 126 Nickel 28 Ni 58.69 124 Copper 29 Cu 63.55 132 Zinc 30 Zn 65.39 122 Gallium 31 Ga 69.72 122 Germanium 32 Ge 72.61 120 Arsenic 33 As 74.92 119 Selenium 34 Se 78.96 120 Bromine 35 Br 79.90 120 Krypton 36 Kr 83.80 116 Rubidium 37 Rb 85.47 220 Strontium 38 Sr 87.62 195 Yttrium 39 Y 88.91 190 Zirconium 40 Zr 91.22 175 Niobium 41 Nb 92.91 164 Molybdenum 42 Mo 95.94 154 Technetium 43 Tc (98) 147 Ruthenium 44 Ru 101.07 146 Rhodium 45 Rh 102.91 142 Palladium 46 Pd 106.42 139 Silver 47 Ag 107.87 145 Cadmium 48 Cd 112.41 144 Indium 49 In 114.82 142 Tin 50 Sn 118.71 139 Antimony 51 Sb 121.76 139 Tellurium 52 Te 127.60 138 Iodine 53 I 126.90 139 Xenon 54 Xe 131.29 140 Cesium 55 Cs 132.91 244 Barium 56 Ba 137.33 215 57-70 * Lutetium 71 Lu 174.97 187 Hafnium 72 Hf 178.49 175 Tantalum 73 Ta 180.95 170 Tungsten 74 W 183.84 162 Rhenium 75 Re 186.21 151 Osmium 76 Os 190.23 144 Iridium 77 Ir 192.22 141 Platinum 78 Pt 195.08 136 Gold 79 Au 196.97 136 Mercury 80 Hg 200.59 132 Thallium 81 Tl 204.38 145 Lead 82 Pb 207.20 146 Bismuth 83 Bi 208.98 148 Polonium 84 Po (209) 140 Astatine 85 At (210) 150 Radon 86 Rn (222) 150 Francium 87 Fr (223) 260 Radium 88 Ra (226) 221 89-102 ** Lawrencium 103 Lr (262) Rutherfordium 104 Rf (267) Dubnium 105 Db (268) Seaborgium 106 Sg (271) Bohrium 107 Bh (272) Hassium 108 Hs (270) Meitnerium 109 Mt (276) Darmstadtium 110 Ds (281) Roentgenium 111 Rg (280) Copernicium 112 Cn (285) Ununtrium 113 Uut (284) Ununquadium 114 Uuq (289) Ununpentium 115 Uup (288) Ununhexium 116 Uuh (293) Ununseptium 117 Uus (294?) Ununoctium 118 Uuo (294) *lanthanides Lanthanum 57 La 138.91 207 Cerium 58 Ce 140.12 204 Praseodymium 59 Pr 140.91 203 Neodymium 60 Nd 144.24 201 Promethium 61 Pm (145) 199 Samarium 62 Sm 150.36 198 Europium 63 Eu 151.97 198 Gadolinium 64 Gd 157.25 196 Terbium 65 Tb 158.93 194 Dysprosium 66 Dy 162.50 192 Holmium 67 Ho 164.93 192 Erbium 68 Er 167.26 189 Thulium 69 Tm 168.93 190 Ytterbium 70 Yb 173.04 187 **actinides Actinium 89 Ac (227) 215 Thorium 90 Th 232.04 206 Protactinium 91 Pa 231.04 200 Uranium 92 U 238.03 196 Neptunium 93 Np (237) 190 Plutonium 94 Pu (244) 187 Americium 95 Am (243) 180 Curium 96 Cm (247) 169 Berkelium 97 Bk (247) Californium 98 Cf (251) Einsteinium 99 Es (252) Fermium 100 Fm (257) Mendelevium 101 Md (258) Nobelium 102 No (259)

Name Graphing the Periodic Table Define the following: GROUPS: Groups are also called columns or families. PERIODS: Periods are also called rows. Background/Explanation: The atomic radius is the distance from the nucleus of an atom out to the furthest valence electron. The atomic radius tells you the size of an atom. The larger the radius, the larger the atom. Procedure: 1. Use the Periodic Table provided to graph the Atomic Radius vs. the Atomic Number for elements 3-20. 2. Use the Periodic Table provided to graph the Atomic Radius vs. the Atomic Number for Groups 1 and 2.

Graph 1: Atomic Number Vs Atomic Radius for elements 3-20 Questions for Graph #1: 1. Within a period, as the atomic number increases, the radius of an atom decreases. 2. What causes your graph to jump from elements 10 to 11 and 18 to 19? (Hint: Look at your Periodic Table!) You are starting a new row on the Periodic Table. 3. What is periodic (look for repeating patterns) about your graph? At the beginning of a row, the atomic radius is the highest and it goes down as you go across the row.

Graph #2: Atomic Number vs. Atomic Radius for Groups 1 & 2 Questions for Graph #2: 4. Within a group, as the atomic number increases, the atomic radius increases. 5. Which generally has larger atoms Group 1 or Group 2? Group 1 6. Where do you think Group 3 would belong on this graph? Draw a dashed line in this location. Group 3 would be a curve just like groups 1 & 2, except that it would be beneath them.

Analysis Questions (questions for BOTH graphs): 7. Going down a group, what is the trend for atomic size? The atom radius increases. 8. Explain the trend form question #7. Give reasons for why it happens. Every time you go down one element in a column, you are adding another energy level to the atom. 9. Going across a period, what is the trend for atomic radius? When you go across a period the atomic radius decreases. 10. Explain the trend form question #9. Give reasons for why it happens. It doesn t make sense that the atomic radius decreases as you go across a row, because at the same time you are adding more stuff (protons, neutrons and electrons) to each atom. You have to remember that the protons and electrons are oppositely charged and that means that they are attracted to each other. You also have to remember that atoms with full outside energy levels (or 8 electrons in the outside energy level are more stable than other atoms. A more stable atom means that the atom is in a lower energy state and that means that the electrons are actually closer to the nucleus (where the protons are located).

A Bonus Trend: Look at the graph below and answer the questions that follow. Boiling & Melting Points of a Group 1. What happens to the boiling and melting points as you go down this column? As you go down the column, the boiling points and melting points increase. 2. Which elements are gases at room temperature? Fluorine and chlorine are gases at room temperature. 3. Which element would be a liquid at room temperature? Bromine is a liquid at room temperature. 4. Which element is a solid at room temperature? Iodine is a solid at room temperature. 5. On the planet Vulcan, room temperature is -20 C. What state will bromine be in at that temperature? Bromine will be a solid at that temperature.

Ions and Ionization Energy Today you are going to learn a little bit more about atoms and, in turn, the Periodic Table. You know that chemical reactions happen. You have seen fireworks exploding, wood burning, food baking and much more. The driving question here is Why do chemical reactions happen? To answer this question we will have to cover a few points: Point #1: Atoms react, and reactions happen, because atoms want to be happy. Here is what makes an atom happy: - Atoms are happy when they have a full outside energy level of electrons or 8 valence electrons. - Some atoms can be happy when they have ZERO electrons. The reason that this makes atoms happy is that when atoms have the outside energy level full or have 8 valence electrons they are the most stable. This is their lowest energy state.

Point #2: Atoms gain or lose electrons in order to reach a state of happiness. Every atom wants to be just like the Noble Gases. To do this they need to gain or lose electrons. Atoms straight off of the Periodic Table have the same number of protons (+ charges) and electrons (- charges). The charges cancel out and the result is that all atoms on the Periodic Table are neutral or have no charge. Here is an example for you: Lithium has an atomic number of 3. This means that it has 3 protons (for an overall charge of +3 ) and 3 electrons (for an over-all charge of -3 ). When you add the charges together you get a net charge of zero ( +3 + -3 = 0). As you can see, a lithium atom straight off the Periodic Table has no charge (it is neutral), but it is it happy? Well, according to the rules, it has to have a full outer energy level or 8 electrons in the outer energy level. Let s look at the Bohr Model for Lithium: If you look at the model, you will notice two things: 1. Lithium has one electron in the outer energy level it isn t happy. 2. Lithium has a full inner energy level. If lithium wants to be happy, it has two options it can gain 7 electrons in order to fill up the outside energy level or it can lose the one electron that it has in the outer level and then it will be left with just its inner energy level which is full. What will lithium do? Will it lose 1 electron or gain 7 more electrons? To answer that question we need to get to Point #3.

Point #3: Atoms are lazy. Atoms will do the least amount of work possible (this reminds me of some students that I know). Lithium is faced with the decision of losing one electron or gaining 7 new ones. Being lazy, it will go with losing one electron. When it does that, you get a Bohr Model that looks like this: Lithium has two electrons in the outside energy level and, since it is the first energy level which only can hold 2 electrons, lithium is, by definition, happy. When you look at the model above, you will note that the happy lithium has a + sign by it. That is because the lithium atom is charged now it has become an ion and that leads us to Point #4. Point #4: Ions are charged atoms. Let s look at lithium before it was happy (right off the Periodic Table) and after it became happy (when it lost the electron). Before: Lithium has 3 protons (+3 charge) and 3 electrons (-3 charge). The over-all charge of the atom is zero ( +3 + -3 = 0). After: Lithium still has 3 protons (+3 charge), but now it only has 2 electrons (-2 charge). The over-all charge is +1 ( +3 + -2 = +1).

Practice Problems 1. For each of the elements listed on the table below, write down how many valence electrons it has, what it could do to become happy, what it will do to become happy and what charge ion it will form. Element Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon Hydrogen Francium Iodine Valence Electrons 1 2 3 4 5 6 7 8 1 1 7 What it could do to become happy 1. Gain 7 electrons 2. Lose 1 electron 1. Gain 6 2. Lose 2 1. Gain 5 2. Lose 3 1. Gain 4 2. Lose 4 1. Gain 3 2. Lose 5 1. Gain 2 2. Lose 6 1. Gain 1 2. Lose 7 1. Gain 0 2. Lose 0 1. Gain 1 2. Lose 1 1. Gain 7 2. Lose 1 What it will do to become happy Ion Charge (Show work!) Lose 1 electron #P + #E (+3) + (-2) = +1 Lose 2 electrons (+4) + (-2) = +2 Lose 3 electrons (+5) + (-2) = +3 Gain 4 electrons Lose 4 electrons Gain 3 electrons Gain 2 electrons Gain 1 electron Nothing Gain 1 electron Lose 1 electron Lose 1 electron 1. Gain 1 2. Lose 7 Gain 1 electron (+6) +(-10) = -4 (+6) + (-2) = +4 (+7) + (-10) = -3 (+8) + (-10) = -2 (+9) + (-10) = -1 (+10) + (-10) = 0 (+1) + (-2) = -1 (+1) + (-0) = +1 (+87) + (-86) = +1 (+53) + (-54) = -1 2. On the table below, fill out how each type of atom typically becomes an ion: Type of Element Metals Non-metals Metalloids Become ions by.. Losing electrons Gaining electrons Gaining or losing electrons

3. What is so special about the elements in the Carbon Family? They can either gain or lose electrons. 4. Hydrogen can do two things to become happy. Based upon that, what other column on the Periodic Table could Hydrogen be placed in? Column #7 (since it can form an ion with a charge of -1 ). Alright, so now you know that atoms want to be happy and what atoms will do to become happy. Some atoms gain electrons and others lose them. Some atoms will do either. This leads us to a new property of atoms to learn about and a new trend to discover on your Periodic Table: First Ionization Energy First ionization energy is defined as the amount of energy that it would take to remove one valence electron from an atom. Based upon what you have learned about atoms and ions so far, it is time to make a prediction. Prediction (circle your choice in the sentence below) Atoms that gain/lose electrons will have the highest first ionization energies. Why did you make the choice that you made?

Graphing First Ionization Energy Use the Periodic Table provided below to make the following graphs. Graph #1: First Ionization Energy vs. Atomic Number for Elements 1-20 1. What is the trend for first ionization energy as you go across a period? It increases. 2. Why do you think it does this? Going across a row/period, you go from atoms that want to lose electrons (metals) to atoms that want to add on more electrons. It makes sense that an atom that wants to get rid of electrons wouldn t hold on to them as tightly as an atom that needs to gain electrons to become stable.

Graph #2 First Ionization Energy vs. Atomic Number for Groups 1&2 1400 First Ionization Energy vs. Atomic Number for Groups 1 & 2 1200 Ionization Energy 1000 800 600 400 Column 1 Column 2 200 0 1 2 3 4 5 6 7 3. What is the trend for first ionization energy as you go down a group? It decreases. 4. Why do you think it does this? Each time you go down a column, you are adding an extra energy level. The attraction between the nucleus and the electrons decreases as they move away from each other. 5. How might first ionization energy help you explain why the atomic radius (yesterday s trend) of the atoms decreases as you go across a period?

6. Atoms that gain electrons in order to become happy (get a full outer energy level or have 8 electrons in the outer level) tend to hold on to their electrons tighter. They pull them closer to the nucleus and that make sit harder to pull them away.